GPU switching

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A classic motherboard with on-board integrated graphics processors, a discrete graphics card can be installed at a PCI slot Acer E360 Socket 939 motherboard by Foxconn.svg
A classic motherboard with on-board integrated graphics processors, a discrete graphics card can be installed at a PCI slot

GPU switching is a mechanism used on computers with multiple graphic controllers. This mechanism allows the user to either maximize the graphic performance or prolong battery life by switching between the graphic cards. It is mostly used on gaming laptops which usually have an integrated graphic device and a discrete video card.

Contents

Basic components

Most computers using this feature contain integrated graphics processors and dedicated graphics cards that applies to the following categories.

Integrated graphics

Also known as: Integrated graphics, shared graphics solutions, integrated graphics processors (IGP) or unified memory architecture (UMA). This kind of graphics processors usually have much fewer processing units and share the same memory with the CPU.

Intel Core i5 processor with integrated HD Graphics 2000 Intel core i5-2500 top IMGP9336 wp.jpg
Intel Core i5 processor with integrated HD Graphics 2000

Sometimes the graphics processors are integrated onto a motherboard. It is commonly known as: on-board graphics. A motherboard with on-board graphics processors doesn't require a discrete graphics card or a CPU with graphics processors to operate.

Dedicated graphics cards

Also known as: discrete graphics cards. Unlike integrated graphics, dedicated graphics cards have much more processing units and have its own RAM with much higher memory bandwidth.

In some cases, a dedicated graphics chip can be integrated onto the motherboards, B150-GP104 for example. Regardless of the fact that the graphics chip is integrated, it is still counted as a dedicated graphics cards system because the graphics chip is integrated with its own memory.

Theory

Figure 1. Motherboard diagram outlining a structure of modern PC computer architecture (typically x86-64-based). Southbridge, Northbridge and busses are visible. Motherboard diagram.svg
Figure 1. Motherboard diagram outlining a structure of modern PC computer architecture (typically x86-64-based). Southbridge, Northbridge and busses are visible.

Most Personal Computers have a motherboard that uses a Southbridge and Northbridge structure.

Northbridge control

The Northbridge is one of the core logic chipset that handles communications between the CPU, GPU, RAM and the Southbridge. The discrete graphics card is usually installed onto the graphics card slot such as PCI-Express and the integrated graphics is integrated onto the CPU itself or occasionally onto the Northbridge.[ citation needed ] The Northbridge is the most responsible for switching between GPUs. The way how it works usually has the following process (refer to the Figure 1. on the right): [1] [2]

  1. The Northbridge receives input from Southbridge through the internal bus.
  2. The Northbridge signals to CPU through the Front-side bus.
  3. The CPU runs the task assignment application (usually the graphics card driver) to determine which GPU core to use.
  4. The CPU passes down the command to the Northbridge.
  5. The Northbridge passes down the command to the according GPU core.
  6. The GPU core processes the command and returns the rendered data back to the Northbridge.
  7. The Northbridge sends the rendered data back to Southbridge.

Southbridge control

The Southbridge is a set of integrated circuits such Intel's I/O Controller Hub (ICH). It handles all of a computer's I/O functions, such as receiving the keyboard input and outputting the data onto the screen. The way how it usually works usually has two steps: [3]

  1. Take in the user input and pass it down to the Northbridge.
  2. (Optional) Receive the rendered data from the Northbridge and output it.

The reason why the second step can be optional is that sometimes the rendered the data is outputted directly from the discrete graphics card which is located on the graphics card slot so there is no need to output the data through the Southbridge.

Main purpose

GPU switching is mostly used for saving energy by switching between graphic cards. The dedicated graphics cards consume much more power than integrated graphics but also provides higher 3D performances, which is needed for a better gaming and CAD experience. Following is a list of the TDPs of the most popular CPU with integrated graphics and dedicated graphics cards.

TDP of Integrated Graphics and Dedicated Graphics Cards [4] [5] [6] [7]
ModelPlatform
Integrated GraphicsDedicated Graphics Cards
Intel TDP Nvidia TDP AMD TDP
CPU Model & FrequencyIntel IGP Serie
Intel Core i7-6700K @ 4.00 GHzIntel HD Graphics 53091WGTX 1080180WRadeon R9 Fury275WDesktop
Intel Core i5-6600K @ 3.50 GHzIntel HD Graphics 53091WGTX 970145WRadeon R9 Nano175W
Intel Core i7-4790K @ 4.40 GHzIntel HD Graphics 460088WGTX 780Ti250WRadeon RX 480150W
Intel Core i7-6700HQ @ 2.60 GHzIntel HD Graphics 53045WGTX 1080165WRadeon R9 M485X125WLaptop
Intel Core i7-6500U @ 2.50 GHzIntel HD Graphics 52015WGTX 980M100WRadeon R9 M470X75W
Intel Core i5-6200U @ 2.30 GHzIntel HD Graphics 52015WGTX 880M103WRadeon R9 M47075W
Intel Core i5-5200U @ 2.20 GHzIntel HD Graphics 550015WGTX 870M103WRadeon HD 7950M50W

The dedicated graphics cards exhibit much higher power consumption than the integrated graphics on both platforms. Disabling them when no heavy graphics processing is needed can significantly lower the power consumption.

Technologies

A classic graphic rendering process with multiple GPU cores Rendering Process.png
A classic graphic rendering process with multiple GPU cores

Nvidia Optimus

Nvidia Optimus™ is a computer GPU switching technology created by Nvidia that can dynamically and seamlessly switch between two graphic cards based on running programs.

AMD Enduro

AMD Enduro™ is a collective brand developed by AMD that features many new technologies that can significantly save power. It was previously named as: PowerXpress and Dynamic Switchable Graphics (DSG). This technology implements a sophisticated system to predict the potential usage need for graphics cards and switch between graphics cards based on predicted need. This technology also introduces a new power control plan that allows the discrete graphics cards consume no energy when idling. [8]

Manufacturers

Integrated graphics

In personal computers, the IGP (integrated graphics processors) are mostly manufactured by Intel and AMD and are integrated onto their CPUs. They are commonly known as: [9] [10]

Dedicated graphics cards

The most popular dedicated graphics cards are manufactured by AMD and Nvidia. They are commonly known as:

Drivers & OS support

Most common operating systems have built-in support for this feature. However, the users may download the updated drivers from Nvidia or AMD for better experience.

Windows support

Windows 7 has built-in support for this feature. The system automatically switches between GPUs depending on the program that's running. However, the user may switch the GPUs manually through device manager or power manager. [11]

Linux support

In the Linux systems, a patch named vga_switcheroo [13] has been added to the Linux kernel since version 2.6.34 in order to deal with multiple GPUs. Here, the switch requires a restart of the X Window System to be taken into account.

Ubuntu Control Center allows the user to access vga_switcheroo functionality through a GUI.

Mac OS support

Mac OS has built-in support for this feature since v10.5 Leopard. Since OS X Mountain Lion, Apple has integrated the GPU monitor into the Activity Monitor. [14]

Existing troubles

See also

Related Research Articles

<span class="mw-page-title-main">Graphics card</span> Expansion card which generates a feed of output images to a display device

A graphics card is a computer expansion card that generates a feed of graphics output to a display device such as a monitor. Graphics cards are sometimes called discrete or dedicated graphics cards to emphasize their distinction to integrated graphics processor on the motherboard or the CPU. A graphics processing unit (GPU) that performs the necessary computations is the main component in a graphics card, but the acronym "GPU" is sometimes also used to erroneously refer to the graphics card as a whole.

<span class="mw-page-title-main">ATI Technologies</span> Canadian technology corporation

ATI Technologies Inc., commonly called ATI, was a Canadian semiconductor technology corporation based in Markham, Ontario, that specialized in the development of graphics processing units and chipsets. Founded in 1985, the company listed publicly in 1993 and was acquired by AMD in 2006. As a major fabrication-less or fabless semiconductor company, ATI conducted research and development in-house and outsourced the manufacturing and assembly of its products. With the decline and eventual bankruptcy of 3dfx in 2000, ATI and its chief rival Nvidia emerged as the two dominant players in the graphics processors industry, eventually forcing other manufacturers into niche roles.

<span class="mw-page-title-main">Chipset</span> Electronic component to manage data flow of a CPU

In a computer system, a chipset is a set of electronic components on one or more integrated circuits that manages the data flow between the processor, memory and peripherals. The chipset is usually found on the motherboard of computers. Chipsets are usually designed to work with a specific family of microprocessors. Because it controls communications between the processor and external devices, the chipset plays a crucial role in determining system performance.

<span class="mw-page-title-main">Coprocessor</span> Type of computer processor

A coprocessor is a computer processor used to supplement the functions of the primary processor. Operations performed by the coprocessor may be floating-point arithmetic, graphics, signal processing, string processing, cryptography or I/O interfacing with peripheral devices. By offloading processor-intensive tasks from the main processor, coprocessors can accelerate system performance. Coprocessors allow a line of computers to be customized, so that customers who do not need the extra performance do not need to pay for it.

<span class="mw-page-title-main">Graphics processing unit</span> Specialized electronic circuit; graphics accelerator

A graphics processing unit (GPU) is a specialized electronic circuit initially designed to accelerate computer graphics and image processing. After their initial design, GPUs were found to be useful for non-graphic calculations involving embarrassingly parallel problems due to their parallel structure. Other non-graphical uses include the training of neural networks and cryptocurrency mining.

<span class="mw-page-title-main">Northbridge (computing)</span> PC chip handling onboard control tasks

In computing, a northbridge is one of two chips comprising the core logic chipset architecture on motherboards for older personal computers. A northbridge is connected directly to a CPU via the front-side bus (FSB) to handle high-performance tasks, and is usually used in conjunction with a slower southbridge to manage communication between the CPU and other parts of the motherboard.

<span class="mw-page-title-main">Southbridge (computing)</span> One of the two chips in the core logic chipset architecture on a PC motherboard

The southbridge is one of the two chips in the core logic chipset on older personal computer (PC) motherboards, the other being the northbridge. As of 2023, most personal computer devices no longer use a set of two chips, and instead have a single chip acting as the 'chipset', for example Intel's Z790 chipset.

<span class="mw-page-title-main">Alienware</span> American computer hardware subsidiary of Dell, Inc.

Alienware is an American computer hardware subsidiary of Dell. Their product range is dedicated to gaming computers and can be identified by their alien-themed designs. Alienware was founded in 1996 by Nelson Gonzalez and Alex Aguila. The development of the company is also associated with Frank Azor, Arthur Lewis, Joe Balerdi, and Michael S. Dell. The company's corporate headquarters is located in The Hammocks, Miami, Florida.

nForce4 Motherboard chipset

The nForce4 is a motherboard chipset released by Nvidia in October 2004. The chipset supports AMD 64-bit processors and Intel Pentium 4 LGA 775 processors.

<span class="mw-page-title-main">Scalable Link Interface</span> Brand name; multi-GPU technology by Nvidia

Scalable Link Interface (SLI) is the brand name for a now discontinued multi-GPU technology developed by Nvidia for linking two or more video cards together to produce a single output. SLI is a parallel processing algorithm for computer graphics, meant to increase the available processing power.

The Intel Graphics Media Accelerator (GMA) is a series of integrated graphics processors introduced in 2004 by Intel, replacing the earlier Intel Extreme Graphics series and being succeeded by the Intel HD and Iris Graphics series.

<span class="mw-page-title-main">Graphics hardware</span>

Graphics hardware is computer hardware that generates computer graphics and allows them to be shown on a display, usually using a graphics card in combination with a device driver to create the images on the screen.

The Xpress 3200 is a revision of the Xpress 200 computer chipset released by ATI. The chipset supports AMD64 processors for Socket 939 and Socket AM2.

AMD 580 chipset series is a computer chipset series designed by the AMD Graphics Product Group, for the AMD processors. It was designed for usage with ATI's CrossFire Multi GPU Technology, with both PCI Express slots running at x16 lanes each.

The AMD 700 chipset series is a set of chipsets designed by ATI for AMD Phenom processors to be sold under the AMD brand. Several members were launched in the end of 2007 and the first half of 2008, others launched throughout the rest of 2008.

<span class="mw-page-title-main">Larrabee (microarchitecture)</span>

Larrabee is the codename for a cancelled GPGPU chip that Intel was developing separately from its current line of integrated graphics accelerators. It is named after either Mount Larrabee or Larrabee State Park in Whatcom County, Washington, near the town of Bellingham. The chip was to be released in 2010 as the core of a consumer 3D graphics card, but these plans were cancelled due to delays and disappointing early performance figures. The project to produce a GPU retail product directly from the Larrabee research project was terminated in May 2010 and its technology was passed on to the Xeon Phi. The Intel MIC multiprocessor architecture announced in 2010 inherited many design elements from the Larrabee project, but does not function as a graphics processing unit; the product is intended as a co-processor for high performance computing.

<span class="mw-page-title-main">AMD Hybrid Graphics</span> Line of discrete and integrated graphics processing units

AMD Hybrid Graphics technology, is a collective brand from AMD for its Radeon line of discrete and integrated GPU, promoting higher performance and productivity while saving energy consumption in GPUs.

<span class="mw-page-title-main">Sony Vaio S series</span>

The VaioS series was a line of notebook computers from Sony introduced in summer 2004. They have been touted as business laptops, and their designs have focused on being thin and light. They also have features friendly to businesspeople, such as TPM chips, matte (anti-glare) displays, RAID SSDs, and extended sheet batteries, as well as continuing to include RJ-45 and VGA (D-Sub) connections.

Nvidia Optimus is a computer GPU switching technology created by Nvidia which, depending on the resource load generated by client software applications, will seamlessly switch between two graphics adapters within a computer system in order to provide either maximum performance or minimum power draw from the system's graphics rendering hardware.

<span class="mw-page-title-main">Dell Inspiron desktop computers</span> Desktop computer series by Dell

On June 26, 2007, Dell released the new Inspiron desktop series, under the Dell Inspiron branding, as a replacement to the Dell Dimension desktop computers.

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